This invention relates to modular scaffolding systems for the construction and maintenance industries.
One example of a modular scaffolding system, shown in U.S. Pat. No. 4,749,060 to Vandelinde entitled "Modular Stage Platform" issued Jun. 7, 1988 employs preassembled stage platforms which are interconnected at their ends with male and female connectors comprising vertical plates extending at opposite ends of such platforms. The connections may be maintained with fasteners including cylindrical rods or connecting pins. The patent discloses a platform in which its side trusses and deck are welded together to form a large box-like structure which cannot be easily transported in a flattened state. Some scaffolding systems have detachable side trusses and decks so that the scaffolding may be transported in a flat, knock down state.
Since scaffolding systems are intended as temporary structures, they are repeatedly assembled, disassembled and moved from place to place, and are exposed to wear and tear during their lifetimes. Additionally, scaffolding is often handled roughly such that components are subject to impact loads and stress concentrations when loaded onto and off of trucks. In such environments, protruding members for interconnecting stage platforms such as male and female connectors located at the ends of the platforms are often problematic because such connectors are often bent or otherwise damaged making interconnection of platforms difficult or impossible, and possibly reducing their strength.
It is desirable that a modular scaffolding system be simple to put together using relatively few parts and flexible assembly procedures with few or no tools. Of course, scaffolding systems also must exhibit uncompromising strength under adverse working conditions. Many presently available scaffolding systems are heavy, cumbersome and hard to move from place to place such as that disclosed in U.S. Pat. No. 4,749,060. Many preassembled stage platforms are modular only to the extent that they are interconnectable with other stage platforms. Such scaffolding systems do not employ exchangeable and interchangeable modular componentry such as detachable side trusses and decks that may be transported in a flat stack on a bed of a pick-up truck and readily erected and connected to one another to form a scaffolding. Moreover, some such stage platforms have welded joints which are subject to undesirably high shear and tensile stresses.